<h3>描述</h3>
<h4>第一步是总览页</h4>
<h3>示例</h3>
<button (click)="start()" tiButton>开始引导</button>

<div class="container">
  <span #introStep1 style="top: 10px; left: 30px">1号新功能</span>
  <span #introStep2 style="top: 200px; left: 80px">2号新功能</span>
  <span #introStep3 style="right: 10px; top: 30px">3号新功能</span>
</div>
<style>
  .container {
    height: 1200px;
    margin: 50px;
    position: relative;
  }

  span {
    position: absolute;
    padding: 4px 8px;
  }
</style>
